Unbreakable Formation

Creatures you control gain indestructible until end of turn.
Addendum — If you cast this spell during your main phase, put a +1/+1 counter on each of those creatures and they gain vigilance until end of turn.

Hedron Archive

{T}: Add {C}{C}.
{2}, {T}, Sacrifice Hedron Archive: Draw two cards.

Selfless Spirit

Flying
Sacrifice Selfless Spirit: Creatures you control gain indestructible until end of turn.

Plains

Phyrexian Altar

Sacrifice a creature: Add one mana of any color.

True Conviction

Creatures you control have double strike and lifelink.

Bontu's Monument

Black creature spells you cast cost {1} less to cast.
Whenever you cast a creature spell, each opponent loses 1 life and you gain 1 life.

Cathars' Crusade

Whenever a creature enters the battlefield under your control, put a +1/+1 counter on each creature you control.

Stonecloaker

Flash
Flying
When Stonecloaker enters the battlefield, return a creature you control to its owner's hand.
When Stonecloaker enters the battlefield, exile target card from a graveyard.

Umbilicus

At the beginning of each player's upkeep, that player may pay 2 life. If they don't, they return a permanent they control to its owner's hand.

Stormfront Riders

Flying
When Stormfront Riders enters the battlefield, return two creatures you control to their owner's hand.
Whenever Stormfront Riders or another creature is returned to your hand from the battlefield, create a 1/1 white Soldier creature token.

Binding Mummy

Whenever another Zombie enters the battlefield under your control, you may tap target artifact or creature.

Signal Pest

Battle cry (Whenever this creature attacks, each other attacking creature gets +1/+0 until end of turn.)
Signal Pest can't be blocked except by creatures with flying or reach.

Rootborn Defenses

Populate. Creatures you control gain indestructible until end of turn. (To populate, create a token that's a copy of a creature token you control.)

Nykthos, Shrine to Nyx

{T}: Add {C}.
{2}, {T}: Choose a color. Add an amount of mana of that color equal to your devotion to that color. (Your devotion to a color is the number of mana symbols of that color in the mana costs of permanents you control.)

Millikin

{T}, Mill a card: Add {C}. (To mill a card, put the top card of your library into your graveyard.)

Ornithopter

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice Mind Stone: Draw a card.

Anointed Procession

If an effect would create one or more tokens under your control, it creates twice that many of those tokens instead.

Gold Myr

Jeskai Barricade

Flash (You may cast this spell any time you could cast an instant.)
Defender
When Jeskai Barricade enters the battlefield, you may return another target creature you control to its owner's hand.

Oketra's Monument

White creature spells you cast cost {1} less to cast.
Whenever you cast a creature spell, create a 1/1 white Warrior creature token with vigilance.

Odric, Lunarch Marshal

At the beginning of each combat, creatures you control gain first strike until end of turn if a creature you control has first strike. The same is true for flying, deathtouch, double strike, haste, hexproof, indestructible, lifelink, menace, reach, skulk, trample, and vigilance.

Palladium Myr

Dust Elemental

Flash (You may cast this spell any time you could cast an instant.)
Flying; fear (This creature can't be blocked except by artifact creatures and/or black creatures.)
When Dust Elemental enters the battlefield, return three creatures you control to their owner's hand.

Bygone Bishop

Flying
Whenever you cast a creature spell with mana value 3 or less, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control.)
Equip {1}

Idol of Oblivion

{T}: Draw a card. Activate only if you created a token this turn.
{8}, {T}, Sacrifice Idol of Oblivion: Create a 10/10 colorless Eldrazi creature token.

Emeria, the Sky Ruin

Emeria, the Sky Ruin enters the battlefield tapped.
At the beginning of your upkeep, if you control seven or more Plains, you may return target creature card from your graveyard to the battlefield.
{T}: Add {W}.

Cloudstone Curio

Whenever a nonartifact permanent enters the battlefield under your control, you may return another permanent you control that shares a permanent type with it to its owner's hand.

Make a Stand

Creatures you control get +1/+0 and gain indestructible until end of turn. (Damage and effects that say "destroy" don't destroy them.)

Conclave Phalanx

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
When Conclave Phalanx enters the battlefield, you gain 1 life for each creature you control.

Scapegoat

As an additional cost to cast this spell, sacrifice a creature.
Return any number of target creatures you control to their owner's hand.

Mace of the Valiant

Equipped creature gets +1/+1 for each charge counter on Mace of the Valiant and has vigilance.
Whenever a creature enters the battlefield under your control, put a charge counter on Mace of the Valiant.
Equip {3}

Ugin's Conjurant

Ugin's Conjurant enters the battlefield with X +1/+1 counters on it.
If damage would be dealt to Ugin's Conjurant while it has a +1/+1 counter on it, prevent that damage and remove that many +1/+1 counters from Ugin's Conjurant.

Kami of False Hope

Sacrifice Kami of False Hope: Prevent all combat damage that would be dealt this turn.

God-Eternal Oketra

Double strike
Whenever you cast a creature spell, create a 4/4 black Zombie Warrior creature token with vigilance.
When God-Eternal Oketra dies or is put into exile from the battlefield, you may put it into its owner's library third from the top.

Endless Atlas

{2}, {T}: Draw a card. Activate only if you control three or more lands with the same name.

Cavalier of Dawn

Vigilance
When Cavalier of Dawn enters the battlefield, destroy up to one target nonland permanent. Its controller creates a 3/3 colorless Golem artifact creature token.
When Cavalier of Dawn dies, return target artifact or enchantment card from your graveyard to your hand.

Crush Contraband

Choose one or both —
• Exile target artifact.
• Exile target enchantment.

Hedron Crawler

{T}: Add {C}. ({C} represents colorless mana.)

Akroma's Blessing

Choose a color. Creatures you control gain protection from the chosen color until end of turn.
Cycling {W} ({W}, Discard this card: Draw a card.)

Manakin

Eiganjo Free-Riders

Flying
At the beginning of your upkeep, return a white creature you control to its owner's hand.

Impassioned Orator

Whenever another creature enters the battlefield under your control, you gain 1 life.

Soul Warden

Whenever another creature enters the battlefield, you gain 1 life.

Venerated Loxodon

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
When Venerated Loxodon enters the battlefield, put a +1/+1 counter on each creature that convoked it.

Dauntless Bodyguard

As Dauntless Bodyguard enters the battlefield, choose another creature you control.
Sacrifice Dauntless Bodyguard: The chosen creature gains indestructible until end of turn.

Mind's Eye

Whenever an opponent draws a card, you may pay {1}. If you do, draw a card.

Loyal Sentry

When Loyal Sentry blocks a creature, destroy that creature and Loyal Sentry.

Concerted Effort

At the beginning of each upkeep, creatures you control gain flying until end of turn if a creature you control has flying. The same is true for fear, first strike, double strike, landwalk, protection, trample, and vigilance.

Imposing Sovereign

Creatures your opponents control enter the battlefield tapped.

Aviary Mechanic

When Aviary Mechanic enters the battlefield, you may return another permanent you control to its owner's hand.

Song of the Worldsoul

Whenever you cast a spell, populate. (Create a token that's a copy of a creature token you control.)

Oblation

The owner of target nonland permanent shuffles it into their library, then draws two cards.

Skyscanner

Flying
When Skyscanner enters the battlefield, draw a card.

Mentor of the Meek

Whenever another creature with power 2 or less enters the battlefield under your control, you may pay {1}. If you do, draw a card.

Valor in Akros

Whenever a creature enters the battlefield under your control, creatures you control get +1/+1 until end of turn.

Blood Clock

At the beginning of each player's upkeep, that player returns a permanent they control to its owner's hand unless they pay 2 life.

Endless One

Endless One enters the battlefield with X +1/+1 counters on it.

Alms Collector

Flash
If an opponent would draw two or more cards, instead you and that player each draw a card.

Thraben Inspector

When Thraben Inspector enters the battlefield, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Generous Gift

Destroy target permanent. Its controller creates a 3/3 green Elephant creature token.

War Priest of Thune

When War Priest of Thune enters the battlefield, you may destroy target enchantment.

Wall of Omens

Defender
When Wall of Omens enters the battlefield, draw a card.

Leonin Relic-Warder

When Leonin Relic-Warder enters the battlefield, you may exile target artifact or enchantment.
When Leonin Relic-Warder leaves the battlefield, return the exiled card to the battlefield under its owner's control.

Solemn Simulacrum

When Solemn Simulacrum enters the battlefield, you may search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.
When Solemn Simulacrum dies, you may draw a card.

Shifting Wall

Defender (This creature can't attack.)
Shifting Wall enters the battlefield with X +1/+1 counters on it.

Reverent Mantra

You may exile a white card from your hand rather than pay this spell's mana cost.
Choose a color. All creatures gain protection from the chosen color until end of turn.

Aetherflux Reservoir

Whenever you cast a spell, you gain 1 life for each spell you've cast this turn.
Pay 50 life: Aetherflux Reservoir deals 50 damage to any target.

Unconventional Tactics

Target creature gets +3/+3 and gains flying until end of turn.
Whenever a Zombie enters the battlefield under your control, you may pay {W}. If you do, return Unconventional Tactics from your graveyard to your hand.

Kor Skyfisher

Flying
When Kor Skyfisher enters the battlefield, return a permanent you control to its owner's hand.

Phyrexian Walker

Kor Cartographer

When Kor Cartographer enters the battlefield, you may search your library for a Plains card, put it onto the battlefield tapped, then shuffle.

Mardu Woe-Reaper

Whenever Mardu Woe-Reaper or another Warrior enters the battlefield under your control, you may exile target creature card from a graveyard. If you do, you gain 1 life.

Benalish Marshal

Memnite

Charming Prince

When Charming Prince enters the battlefield, choose one —
• Scry 2.
• You gain 3 life.
• Exile another target creature you own. Return it to the battlefield under your control at the beginning of the next end step.

Benevolent Bodyguard

Sacrifice Benevolent Bodyguard: Target creature you control gains protection from the color of your choice until end of turn.

Soul's Attendant

Whenever another creature enters the battlefield, you may gain 1 life.

Custodi Squire

Flying
Will of the council — When Custodi Squire enters the battlefield, starting with you, each player votes for an artifact, creature, or enchantment card in your graveyard. Return each card with the most votes or tied for most votes to your hand.

Pearl Medallion

White spells you cast cost {1} less to cast.

Emancipation Angel

Flying
When Emancipation Angel enters the battlefield, return a permanent you control to its owner's hand.

Karmic Guide

Flying, protection from black
Echo {3}{W}{W} (At the beginning of your upkeep, if this came under your control since the beginning of your last upkeep, sacrifice it unless you pay its echo cost.)
When Karmic Guide enters the battlefield, return target creature card from your graveyard to the battlefield.

Resolute Watchdog

Defender
{1}, Sacrifice Resolute Watchdog: Target creature you control gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)

Whitemane Lion

Flash
When Whitemane Lion enters the battlefield, return a creature you control to its owner's hand.

Suture Priest

Whenever another creature enters the battlefield under your control, you may gain 1 life.
Whenever a creature enters the battlefield under an opponent's control, you may have that player lose 1 life.

Children of Korlis

Sacrifice Children of Korlis: You gain life equal to the life you've lost this turn. (Damage causes loss of life.)

Shield Sphere

Defender
Whenever Shield Sphere blocks, put a -0/-1 counter on it.

Erratic Portal

{1}, {T}: Return target creature to its owner's hand unless its controller pays {1}.

Ancestral Statue

When Ancestral Statue enters the battlefield, return a nonland permanent you control to its owner's hand.